The Demodex folliculorum mite is a type of parasite that lives on humans. Most of the time, these mites are harmless and will go unnoticed. However, larger numbers of D. folliculorum mites can cause unwanted symptoms and skin problems.
D. folliculorum mites live in or around hair follicles, feeding on the dead skin cells, oils, and hormones that build up there. These mites usually live on the face, including the eyelids and eyelashes.
D. folliculorum mites are more common in males than in females, with people aged 20–30 years old the most likely to be affected.
In this article, we look at what causes D. folliculorum mites to become a problem and the conditions associated with their presence. We also cover diagnosis and treatment, including home remedies.
D. folliculorum mites are usually harmless but can cause problems for people with weakened immune systems.
Therefore, people at risk of experiencing symptoms include those who:
- are taking corticosteroids, such as prednisone
- have a history of cancer or liver disease
- are living with HIV
Some other people may be genetically susceptible to D. folliculorum and thus more sensitive to the presence of the mites.
Also, D. folliculorum mites are sometimes present in greater numbers in people with certain skin conditions. Examples of these include:
Rosacea is an inflammatory skin condition that causes facial flushing, redness, and dry lesions on the face.
Some studies have found that a person with rosacea can sometimes have four times more Demodex mites on their face than someone without the condition. Among people with rosacea, those with subtype 1 are more likely to have a high number of these mites on their skin.
D. folliculorum mites have also been found in the tear ducts of people with ocular rosacea, which is a type of rosacea that affects the eyes.
Androgenetic alopecia is an inherited hair-loss condition that affects both men and women. It has been suggested that a chemical produced by the mites may trigger an inflammatory reaction that affects hair follicles. Although Demodex mites do not cause androgenetic alopecia, they may worsen the condition.
Non-specific facial dermatitis
Increased numbers of Demodex mites are also associated with symptoms of non-specific dermatitis on the face. These symptoms include itching, acne-like blemishes, and spots around the lips.
Large numbers of D. folliculorum mites can cause rosacea-like symptoms on the skin of the face. These symptoms include:
- acne-like blemishes
- rough-feeling skin
- eye redness
The symptoms caused by D. folliculorum mites are sometimes mistaken for acne or severe skin dryness.
A doctor will start the diagnosis of D. folliculorum by taking a medical history and examining the skin.
The mites are too small to be seen with the naked eye, so the doctor will usually do a skin biopsy. This involves taking a sample of the skin and examining it under a microscope.
It is important to determine the quantity of mites living on the skin. A small number of mites is unlikely to be the cause of an individual's skin problems.
D. folliculorum mites are more likely to occur on the face. This can make treatment more challenging because the skin there is very sensitive.
A doctor may recommend treatment with creams such as crotamiton or permethrin. These are topical insecticides that can kill mites and so reduce their numbers. The doctor may also prescribe topical or oral metronidazole, which is an antibiotic medication.
A person can clean around their eyes using Demodex facial wipes or towelettes. Suitable products include Cliradex and Demodex Control. These products and others are available online.
Doctors may also apply a high-concentration alcohol solution to a person's face. This brings the Demodex mites to the surface. The doctor can then apply substances to the skin that kill the mites and treat the condition.
For people who have a severely weakened immune system, a doctor may prescribe ivermectin.
There are also some preventive measures that a person can take at home. These include:
- Washing the face twice daily with a gentle cleanser. Scrubbing the eyelids with baby shampoo may also help.
- Avoiding oil-based cleansers and greasy makeup, which can provide further "food" for the mites.
- Exfoliating once or twice a week to remove dead skin cells.
Keeping the skin clean and dry as well as addressing any underlying conditions may help to reduce the number of D. folliculorum mites.
For most people, the presence of D. folliculorum mites on the face is harmless.
However, in larger numbers, these mites can cause rosacea-like symptoms. Individuals with certain skin conditions or weakened immune systems are at greater risk of developing these symptoms.
A doctor can do a skin biopsy to determine if a person is living with an abnormally high level of mites. Treatment involves cleaning the face regularly and using various medications to kill the mites.